Lung and Breast Cancer Detection may benefit by the Use
of Dogs

January 6th
2006

Household dogs

Both breast and lung cancer are the leading causes of cancer death
worldwide. It may be possible to quickly screen people in early stages
of the disease using dogs. It appears dogs have an extraordinary
scenting ability for both early and late stage cancers.

According to a study led by Michael McCulloch of the Pine Street
Foundation in San Anselmo California, and Tadeusz Jezierski of the
Polish Academy of Sciences, Institute of Genetics and Animal Breeding,
dogs can detect the cancers with accuracy (sensitivity and specificity)
between 88 and 97 percent.

Scientists were first became aware to the idea of using canines for
detection when a dog alerted its owner to the presence of a melanoma by
constantly sniffing the skin lesion. The canine olfactory
discrimination can identify chemicals that are diluted as low as “parts
per trillion”.

The researchers used five household dogs for this study. They were able
to train the dogs within three weeks to detect lung or breast cancer by
sniffing the breath of the cancer patients.

The study included 86 cancer patients; 55 with lung cancer and 31 with
breast cancer. They took breath samples for these patients and 83
control subjects that did not have cancer. All of the cancer patients
had recently been diagnosed with the disease through biopsy-confirmed
after conventional methods of screening such as a mammogram, or CAT
scan. None had yet undergone any chemotherapy treatment.

All participants gave breath samples that were kept in a tube. The dogs
were trained to give positive identification of a cancer patient by
sitting or lying down directly in front of the test station that
contained the positive sample. The dogs were trained to ignore the
other samples.

According to the study, high accuracy persisted even after the results
were adjusted to take into account whether the lung cancer patients were
currently smokers. The researchers believe that breath analysis has
“the potential to provide a substantial reduction in the uncertainty
currently seen in cancer diagnosis, once further work has been carried
out to standardize and expand this methodology.”

Standard, humane methods of dog training employing food rewards and a
clicker, as well as assessment of the dog's behavior by observers
blinded to the identity of the cancer patient and control samples, were
used in the experiment. This was taken from research originally
published in the journal Integrative Cancer Therapies. The journal is
published by Sage Publications.